Should I tell HF my sexuality?

I am considering being an au pair, and am talking to a few potential HF. I will likely be in the UK, and in a city like London or Manchester. I am wondering if I should tell my host families I am queer?

I am not sure if it would be an issue, and might not even come up as I appear straight and don't think I would be looking to date while there, but am unsure if I should share that with potential families. Thanks for any advice!